Is Biochar a miracle material?
It certainly sounds it. The creation process generates more heat than it uses- meaning manufacture could be self sustaining, or used as energy generation. Once made, it acts as a form of carbon capture, putting it back into the ground. And once in the ground, it can aid water retention, improve soil structure, and aid access to nutrients.
There are some potential issues, mainly around the possibility of contamination depending upon the feed stock, but this sounds like a technology we should all be thinking about.